Auxiliary draft for furnaces.



No. 740,509. I Y PATENTED ocT. 6, 1903;.

- T.-YOUNG. Y

AUXILIARY DRAFT FOR FURN-AGES.

APPLICATION FILED JUNE 8. 1903.

N0 MODEL.

. 7 Thomas fou /Lg y I mgfi U ITED STATES Patented October 6, 1903.

" PATENT OFFICE.

' 'AUXILIARY' DRAFT FOR FURNACES.

SPECIFICATION forming part of Letters Patent No. 740,509, dated October 6, 1903.

Application filed June 8, 1903. Serial No. 160,4;82- (No model.)

New York, have invented certain new and useful Improvements in Auxiliary Draft for Furnaces, of which the following is a specification.

The invention relates to such improvezo ments; it and consists of the novel construction and combination of parts hereinafter described and subsequently claimed.

Reference may be had to the accompanying drawings, and the reference characters t5 marked thereon, which form a part of this specification.

Similar characters refer to similarvparts in the several figures.

Figure 1 of the drawings is a view inside elevation and partly broken away and shown in central vertical longitudinal section of .a

boiler and furnace provided'with my improved Fig. 2 is a view in front draft apparatus.

Fig. 3 is a horizontal elevation of the same.

section of the same, taken on the broken line 3 3 in Fig. 1. Fig. 4 is a vertical cross-section of the same, taken on the broken line i 4 in Fig. 1.

The object and nature of the invention will 0 appear in connection with the 'following description.

1 represents a steam-boiler of ordinary form mounted above a furnace, of which 2 is the fire-box, 3 the ash-pit, and e the bridge-wall,

all ofwhich may be constructed and arranged in the usual manner.

In carrying out my invention I extend a pair of parallel pipes 5 transversely of the flue-space between the bridge-wall and boiler,

0 which pipes communicate at their opposite ends with air-chambers 7, said parts being mounted in fire-clay 8, as shown in Fig. 4, so

as to wholly close the space between the bridge-wall and bottom of the boiler except 5 for the opening 9 between said pipes, through which the products of combustion are obliged to pass from the fire-box to the combustionchamber 10. These pipes 5 are provided each with a row of perforations 6, opening rearwardly and convergent, those of one pipe toward those of another, as shown in Fig. l. p A pair of air-pipes 12 extend along the opposite. sides of the fire-box from the respective air-chambers 7, opening exteriorly of the face-plate 13.0f the furnace, which is provided with doors '01 valves 11, adapted to close said open endsof the pipes.

When the doors 11 are open, the main draft from the fire-box rearwardly throughthe. opening 9 and combustion-chamber 10 will create a current of air passing inwardly through the pipes 12 into the air-chambers 7 and thence through the pipes 5 and out through the apertures 6, where the air mingles with the gases from the fire-box, furnishingan additional supply of oxygen, whereby combustion is facilitated. The air in passing through the pipes 13, air-chambers 7, and pipes 5,'all of which are exposed to the heated products of combustion,'becomes highly heated, in which heated condition it is well adapted to promote the combustion of the gases from the fire-box. r

The arrangement. of the openings in the pipes 5insures the air-currents passing out therethrough to be thoroughly mixed and incorporated with the gases from the fire-box.

When desired, steam may be admitted from the boiler into theair-pipes 12 through the steam-pipe '14, controlled by valve 15.

What I claim as new, and desire to secure by Letters Patent; is--' 1. In a furnace, the combination with the fire-box; and bridge-wall; of 'a pair of airchambers erected upon the bridge-wall at opposite ends of the same; a pair of pipes extending horizontally'from one of said airchambers to the other located one above and the other below the draft-space'above the bridge-wall, said pipes being provided on their neighboring sides with apertures; and a pair of inlet-pipes extending within the firebox from the respective'air-chambers along the opposite sides of the fire-box opening exteriorly of the furnace, and means for closing the spaces between the lower pipe and bridgewall, the upper pipe and superstructure, and the air-chambers and the respective sides of the furnace, substantially as described.

2. In a furnace, the combination with the fire-box, bridge-wall and boiler; of a pair ofair-chambers erected upon the bridge-wall at opposite'ends of the same; a pair of pipes extending horizontally from one of i said airchambers to the other located one above and the other below the draft-space above the bridge-wall, said pipes being provided on their neighboring sides with apertures; a pair 5 of inlet-pipes extending within the fire-box from the respective air-chambers along the opposite sides of the fire-box opening exteriorly of the furnace; means for closing the spaces between the lower pipe and bridge 10 wall, the upper pipe and boiler, and the airchambers and respective sides of the furnace;

and a valve-controlled pipe leading from the boiler to one of said inlet-pipes, substantially as described.

In testimony whereof I have hereunto set I5 my hand this 16th day of May, 1903.

THOMAS YOUNG.

Witnesses:

FRANK C. CURTIS, E. M. OREILLY. 

